1. Field of the Invention
The present invention relates to an image forming apparatus such as a copying machine, and more particularly to a system for transmitting information to an external equipment of the image forming apparatus.
2. Description of the Prior Art
In a prior art copying machine, a user is informed of operation procedures of the machine or operation states of the machine through display means in a control panel. Displays by patterns are designed to inform the user visually and they are effective information transmission means to an unexperienced user. However, when more information items are to be represented by displays, the display designs must be complex or the effect of displays may not be fully attained if the user does not pay attention to the displays or leaves the site of the copying machine during a continuous copy operation. Accordingly, in order to call a user's attention or as a guidance to inform an end of wait time of the copying machine to persons around the copying machine, it is effective to provide an audio announcing means by speech synthesization as the information transmitting means. However, in an office in which the copying machine is usually in use, a frequent audio announcement may be a disturbing noise source to persons other than the user of the copying machine. It also may be one-way information from the copying machine to a distant person.